Touch panels are often used in electronic display systems as a replacement or supplement to a conventional keyboard and/or a mouse. Touch panels are generally intuitive to use and may require comparatively little training to operate. For example, a user can implement a complex sequence of instructions by simply pressing a touch screen at a location identified by an appropriate icon. The functionality of the icon can be changed by manipulating the supporting software according to the application.
An integral part of a touch system is the mechanism for detecting the location of a touch applied by a user. The detection of touch locations may be based on different technologies. Exemplary technologies include resistive, capacitive, force, infrared (IR), and surface acoustic waves (SAW).
Touch panels are often characterized by several attributes including size, ease of use, resolution, optical performance, and cost. Demand for touch panel devices for user input has increased as the variety of electronic devices has increased, as the desire for portable devices has increased, as desk top and other space has become more limited, and as the functionality of touch screens has improved and expanded.